4. THE STANDARD SYLLABUS
4.5. PART V: ASSESSMENT OF EXTERNAL AND INTERNAL
Objective: To enable the students to measure, monitor, calculate and interpret the doses to individuals arising from external exposure, including designing a monitoring programme for individual dose assessment and for the workplace. To enable the participants to use appropriate techniques to assess the doses to individuals arising from intakes of radionuclides in simple cases of internal contamination.
4.5.1. Content
Module Content
Learning Objective
(No.) V.1. Assessment
of occupational exposure due to external sources of radiation
The monitoring programmes for individual dose assessment
Design of monitoring programmes Personal dosimetry
Assessments of effective dose in various external exposure conditions: practical approximations
Integrating personal dosimeters (TLD, film, condenser chambers, etc.) calibrated for personal dose equivalent; use of electronic personal dosimeters; performance requirements for personal dosimeter
Whole body, extremities and skin dosimetry Routine, special, accidental exposure assessment
Analysis of uncertainties: (Type A) inhomogeneity of detector sensitivity readings due to limited sensitivity and background, variability of detector readings at zero dose;
(Type B) energy dependence, directional dependence, non-linearity of the response, fading due to temperature and humidity, effects due to exposure to light, or to other types of ionizing radiation, mechanical shock, calibration errors, variation in local natural background
Dose reconstruction techniques
Accident dosimetry; cytogenetic; EPR; TLD dose construction with Alderson phantoms; criticality dosimetry Monitoring programme for the work place
Routine, task related and special monitoring; fixed and portable monitors; monitoring for work planning purposes;
monitoring to detect changes in the working environment;
monitoring systems for radiation fields, for surfaces; use of ambient dose equivalent and directional dose equivalent Interpretation of measurements
LO.V.1.01
Module Content special monitoring by external exposure; routine, task related and special monitoring
Calibration
Calibration of radiation beam; Bragg-Gray cavity principle;
measurement of absorbed dose with ionization in gas filled cavity; electronic equilibrium; composition of homogeneous cavity; large cavity; small cavity;
recombination effects; correction factors for determination of absorbed dose to water in photon and electron beams Primary and secondary standards; sources used for calibration; routine testing of equipment, performance testing, type testing
Quality management system
Quality control procedures; intercomparison; proficiency test
Primary and secondary standards; sources used for calibration; routine testing of equipment, performance testing, type testing
V.2. Assessment of occupational exposure due to intakes of radionuclides
Modes of intake
Inhalation (particle sizes, AMAD, determination of size distribution of aerosols), ingestion and absorption through skin or wounds
Special case of tritiated water and vapour: intake through skin of splashed water and of vapour and respiratory intake Intakes of radionuclides by workers; intakes of radionuclides by members of the public
Introduction to biokinetic models used by ICRP
Quantitative aspects of intake; uptake into blood and transport to various organs; deposition in organs
Modelling by compartment models; relationships between compartments as one basis for specifying monitoring procedures; retention and elimination; exponential compartments, biological half-life and effective half-life Biokinetic models for internal exposure assessment: ICRP models (reference individual) and relevant parameters;
human respiratory model (HRTM); human alimentary tract model (HATM); entry through wounds and intact skin;
Module Content
Learning Objective
(No.) overview on systemic models
Monitoring programme
Monitoring programme: need, design of a routine monitoring programme, methods of measurement, frequency of monitoring, reference levels, special monitoring
Workplace monitoring: surface and air monitoring; the concept of Derived Air Concentration (DAC)
Individual monitoring - direct methods: principles;
measurement geometry: whole body, thyroid, lung;
methods of detection; measurement procedures
Individual monitoring - indirect methods: biological samples (urine, faeces, breath, blood, nose blows, tissue sample); normalization of samples; physical samples (air samples, surface samples); handling methods; methods of analysis (radiochemical separation, detection)
Performance requirements for detection systems in internal dosimetry
Calculation of committed effective dose
Committed effective dose; committed effective dose per unit of intake; committed effective dose per unit intake in the standard adult and as a function of age; consistency of the measurements with biokinetic models
Calculation of the organ contribution to the effective dose Primary and secondary limits; special case of radon and radon progeny
Introduction to guidelines (EURADOS) and software for internal dose calculation (characteristics and availability) Calibration
Calibration for direct and indirect measurement techniques Quality management system
Quality control procedures; intercomparison; proficiency test
V.3. Assessment of the public exposure
Basic concepts
Exposure pathways; critical groups and representative person; generic methods for assessing doses; uncertainties in dose assessments
Assessment of the public exposure due to radioactive discharges to the environment
LO.V.3.01
Module Content
Learning Objective
(No.) Monitoring strategy: monitoring at source and
environmental monitoring; sampling technics and monitoring quantities; interpretation of monitoring results Examples of application to different sources: medical facilities, radioisotope production plants, waste management facilities, nuclear installations
Assessment of the public exposure due to other scenarios Scenarios for public exposure and identification of parameters important for the assessment. Graded approach to public exposure assessment
4.5.2. Learning Objectives
Module
Learning Objectives
No. Description
On completion of the module, student will be able to:
V.1. Assessment of occupational exposure due to external sources of radiation
LO.V.1.01 design an individual monitoring programme.
LO.V.1.02 describe the different types of personal dosimeter and under what circumstances each is suitable.
LO.V.1.03 interpret dosimeter results.
LO.V.1.04 identify the circumstances where dosimeter results may not provide an adequate estimate of dose.
LO.V.1.05 explain the concepts behind acceptable accuracy and uncertainty, and be able to apply these concepts to determining the uncertainties and detection limits for practical dosimetry systems.
LO.V.1.06 specify the measurement techniques that can be used for accident dosimetry.
LO.V.1.07 describe basic workplace monitoring principles, and be able to determine monitoring methods that can be used as part of the program for assessment of exposure due to external radiation and intake of radionuclides.
LO.V.1.08 describe radiation protection instrument calibration and test techniques and requirements.
V.2. Assessment of occupational exposure due to intakes of radionuclides
LO.V.2.01 summarize the principles involved in development and use of biokinetic models, as well as the need for individual specific models when intakes approach relevant limits.
Module
Learning Objectives
No. Description
On completion of the module, student will be able to:
LO.V.2.02 describe the principles and criteria used to determine the need for monitoring for internal exposure assessment.
LO.V.2.03 explain the principles and techniques that are used for the direct measurement of radioactive material deposited in the human body.
LO.V.2.04 describe indirect monitoring principles and limitations and know how to select the appropriate measurement techniques and assessment methods.
LO.V.2.05 evaluate information provided by a dosimeter or a measurement of intake, with special emphasis on the indication that a high or unusual exposure occurred, and to identify those steps that may need to be taken.
V.3. Assessment of the public exposure
LO.V.3.01 specify methods to assess dose to the public.
4.5.3. Practical exercise
No Practical exercise Type
V-1. Development of a routine monitoring programme (internal and external exposures)
Case study V-2. Interpretation of measurements made with a personal
dosimeter
Case study V-3. Demonstration of practical monitoring systems for areas,
surfaces and air
Demonstration V-4. Calibration of different dosimeters in secondary standard
dosimetry laboratory (SSDL) Technical
visit to a SSDL V-5. Measurement of the radionuclide content of the body by
whole body counting Technical
visit to a whole body counting facility V-6. Measurement of radionuclides using bioassay techniques –
associated quality assurance and quality control procedures Laboratory exercise V-7 Calculation of internal doses using ICRP models for acute
contamination with specific radionuclide Exercises
V-8 Thyroid monitoring Laboratory exercise V-9 Radon/Thoron monitoring using passive and active methods Laboratory
exercise 4.5.4. Bibliography to Part V
BELL S., A Beginner's Guide to Uncertainty of Measurement, NPL Measurement Good Practice Guide No. 11 (Issue 2), National Physical Laboratory, Teddington (2001).
CASTELLANI C.M., MARSH J.W., HURTGEN C., BLANCHARDON E., BERARD P., GUISSANI A., LOPEZ M.A., IDEAS Guidelines (Version 2) for the Estimation of Committed Doses from Incorporation Monitoring Data, EURADOS Report 2013-01, ISSN 2226-8057, Braunschweig (2013).
EUROPEAN COMMISSION, FOOD AND AGRICULTURE ORGANIZATION OF THE UNITED NATIONS, INTERNATIONAL ATOMIC ENERGY AGENCY, INTERNATIONAL LABOUR ORGANIZATION, OECD NUCLEAR ENERGY AGENCY, PAN AMERICAN HEALTH ORGANIZATION, UNITED NATIONS ENVIRONMENT PROGRAMME, WORLD HEALTH ORGANIZATION, Radiation Protection and Safety of Radiation Sources: International Basic Safety Standards, IAEA Safety Standards Series No. GSR Part 3, IAEA, Vienna (2014).
INTERNATIONAL ATOMIC ENERGY AGENCY, Direct Methods for Measuring Radionuclides in the Human Body, Safety Series No. 114, IAEA, Vienna (1996).
- Calibration of Radiation Protection Monitoring Instruments, Safety Series No. 16, IAEA, Vienna (2000).
- Indirect Methods for Assessing Intakes of Radionuclides Causing Occupational Exposure, Safety Reports Series No. 18, IAEA, Vienna, (2002).
- Methods for Assessing Occupational Radiation Doses due to Intakes of Radionuclides, Safety Reports Series No. 37, IAEA, Vienna, (2004).
- Environmental and Source Monitoring for Purposes of Radiation Protection, IAEA Safety Standards Series No. RS-G-1.8, IAEA, Vienna (2005).
- Intercomparison of Personal Dose Equivalent Measurements by Active Personal Dosimeters, IAEA TECDOC Series No. 1564, IAEA, Vienna, (2007).
- Measurement Uncertainty, IAEA TECDOC Series No. 1585, IAEA, Vienna (2008).
- Determination and Interpretation of Characteristic Limits for Radioactivity Measurements - Decision Threshold, Detection Limit and Limits of the Confidence Interval, IAEA Analytical Quality in Nuclear Applications Series No. 48, IAEA, Vienna (2018).
- Radiation Protection of the Public and the Environment, IAEA Safety Standards Series No.
GSG-8, IAEA, Vienna (2018).
- Prospective Radiological Environmental Impact Assessment for Facilities and Activities, IAEA Safety Standards Series No. GSG-10, IAEA, Vienna (2018).
INTERNATIONAL ATOMIC ENERGY AGENCY, INTERNATIONAL LABOUR OFFICE, Occupational Radiation Protection, IAEA Safety Standards Series No. GSG-7, IAEA, Vienna (2018).
INTERNATIONAL ATOMIC ENERGY AGENCY, INTERNATIONAL LABOUR ORGANIZATION, PAN AMERICAN HEALTH ORGANIZATION, WORLD HEALTH ORGANIZATION, Radiation Protection and Safety in Medical Uses of Ionizing Radiation, IAEA Safety Standards Series No. SSG-46, IAEA, Vienna (2018).
INTERNATIONAL COMMISSION ON RADIOLOGICAL PROTECTION, Human Respiratory Tract Model for Radiological Protection, ICRP Publication 66. Ann. ICRP 24 (1-3) (1994).
- General Principles for the Radiation Protection of Workers, ICRP Publication 75. Ann. ICRP 27 (1) (1997).
- Human Alimentary Tract Model for Radiological Protection, ICRP Publication 100. Ann.
ICRP 36 (1-2) (2006).
- Conversion Coefficients for Radiological Protection Quantities for External Radiation Exposures, ICRP Publication 116, Ann. ICRP 40(2-5) (2010).
- Occupational Intakes of Radionuclides: Part 1, ICRP Publication 130. Ann. ICRP 44(2) (2015).
- Occupational Intakes of Radionuclides: Part 2, ICRP Publication 134. Ann. ICRP 45(3/4), (2016).
- Occupational Intakes of Radionuclides: Part 3, ICRP Publication 137. Ann. ICRP 46(3/4) (2017).
INTERNATIONAL ORGANIZATION FOR STANDARDIZATION, Determination of the characteristic limits (decision threshold, detection limit and limits of the confidence interval) for measurements of ionizing radiation -- Fundamentals and application, ISO 11929:2010, ISO, Geneva (2010).
NATIONAL COUNCIL ON RADIATION PROTECTION AND MEASUREMENTS, Development of a Biokinetic Model for Radionuclide-Contaminated Wounds and Procedures for Their Assessment, Dosimetry and Treatment, NCRP report 156, NCRP, Bethesda (2006).
-Uncertainties in Internal Radiation Dose Assessment, Report No. 164, NCRP, Bethesda (2009).
4.6. PART VI: PLANNED EXPOSURE SITUATIONS - GENERIC REQUIREMENTS